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Alsemeh AE, Ahmed MM, Fawzy A, Samy W, Tharwat M, Rezq S. Vitamin E rescues valproic acid-induced testicular injury in rats: Role of autophagy. Life Sci 2022; 296:120434. [DOI: 10.1016/j.lfs.2022.120434] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 02/13/2022] [Accepted: 02/22/2022] [Indexed: 12/19/2022]
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2
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Qi Z, Liu Y, Yang H, Yang X, Wang H, Liu B, Yuan Y, Wang G, Xu B, Liu W, Xu Z, Deng Y. Protective role of m 6A binding protein YTHDC2 on CCNB2 in manganese-induced spermatogenesis dysfunction. Chem Biol Interact 2022; 351:109754. [PMID: 34822792 DOI: 10.1016/j.cbi.2021.109754] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 10/22/2021] [Accepted: 11/16/2021] [Indexed: 01/16/2023]
Abstract
Human infertility has become the third largest serious disease in the world, seriously affecting the quality of human fertility. Studies have shown that manganese (Mn) can accumulate in the testis through the blood-testicular barrier and damage the male reproductive system. However, the mechanism has not been explored clearly. Recent studies have reported that YTH domain-containing 2 (YTHDC2) can regulate reproductive function. However, none has explored the role of YTHDC2 in Mn-induced reproductive toxicity. The present study investigated whether YTHDC2/CyclinB2 (CCNB2) pathway participates in Mn-induced reproductive toxicity using Kunming mice, spermatogonia, and the seminal plasma of male workers. The mice were received intraperitoneal (i.p.) injections of 0, 12.5, 25, and 50 mg/kg MnCl2 once daily for 2 weeks. The cells were treated with 0, 100, 200 and 400 μM MnCl2 for 24 h. Here, we found that occupational Mn exposure significantly increased Mn levels in the seminal plasma of male workers, while decreased sperm density, semen quality, and the levels of YTHDC2, CCNB1, and CCNB2. We found that Mn can inhibit the YTHDC2/CCNB2 signaling pathway and block the G2/M phase of the cell cycle. Moreover, the morphology of cells and the histomorphology of mice testis were injured. Notably, over-expression (OE) of YTHDC2 increased CCNB2 levels, reduced cell cycle arrest, and improved reproductive toxicity after Mn exposure. These findings suggest that the YTHDC2/CCNB2 signaling pathway participates in Mn-induced reproductive toxicity, and OE of YTHDC2 can mitigate the toxicity of Mn.
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Affiliation(s)
- Zhipeng Qi
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, Liaoning, People's Republic of China.
| | - Yanan Liu
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, Liaoning, People's Republic of China; Department of Preventive Health, Zhuhai People's Hospital (Zhuhai Hospital Affiliated with Jinan University), Zhuhai, Guangdong, People's Republic of China.
| | - Haibo Yang
- Department of Occupational Diseases, Linyi People's Hospital, Shandong, People's Republic of China.
| | - Xinxin Yang
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, Liaoning, People's Republic of China.
| | - Haiying Wang
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, Liaoning, People's Republic of China.
| | - Bingchen Liu
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, Liaoning, People's Republic of China.
| | - Yuan Yuan
- Center of Experiment, School of Public Health, China Medical University, Shenyang, Liaoning, People's Republic of China.
| | - Gang Wang
- Center of Experiment, School of Public Health, China Medical University, Shenyang, Liaoning, People's Republic of China.
| | - Bin Xu
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, Liaoning, People's Republic of China.
| | - Wei Liu
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, Liaoning, People's Republic of China.
| | - Zhaofa Xu
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, Liaoning, People's Republic of China.
| | - Yu Deng
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, Liaoning, People's Republic of China.
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Correia TG, Vieira VARO, de Moraes Narcizo A, Zampieri RA, Floeter-Winter LM, Moreira RG. Endocrine disruption caused by the aquatic exposure to aluminum and manganese in Astyanax altiparanae (Teleostei: Characidae) females during the final ovarian maturation. Comp Biochem Physiol C Toxicol Pharmacol 2021; 249:109132. [PMID: 34246795 DOI: 10.1016/j.cbpc.2021.109132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 06/16/2021] [Accepted: 07/04/2021] [Indexed: 12/19/2022]
Abstract
Aluminum (Al) and manganese (Mn) can be toxic to aquatic biota and cause endocrine disruption in fish, affecting reproduction. This study evaluates the physiological responses of the ray-finned teleost fish Astyanax altiparanae vitellogenic females after acute exposure (96 h) to Al and Mn (alone and combined) in acid pH followed by the same period of exposure to metal-free water in neutral pH. The aim of this second period of exposure was to assess the recovery capacity from the toxic effects these metals. Five experimental groups were established: a control in neutral pH (Ctrl), and acidic pH (Ac), aluminum (Al), manganese (Mn), and Al + Mn groups, maintaining the acidic pH in the groups to which metals were added. The following biological parameters were evaluated: metal tissue concentration, relative fecundity (RF: absolute fecundity/body mass). Plasma levels of cortisol (proxy for stress) and 17α hydroxyprogesterone (17α-OHP), and gene expression of pituitary lhβ mRNA (proxies for final maturation) were measured to evaluate endocrine disruption. In the synchronic exposure, the presence of Mn potentiated the accumulation of Al in gills. The females from acidic pH and Al groups showed a reduced RF. Exposure to Al and Mn triggered an endocrine disruption response, evidenced by a decrease in the plasma concentration of 17α-OHP and cortisol. Despite this anti-steroidogenic effect, no changes occurred in the pituitary gene expression of lhβ. The endocrine changes and the metal accumulation were temporary, while the impacts on RF under the experimental conditions suggest permanent impairment in the reproduction of this species.
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Affiliation(s)
- Tiago Gabriel Correia
- Instituto de Biociências, Departamento de Fisiologia, Universidade de São Paulo (USP), São Paulo, SP, Brazil.
| | | | - Amanda de Moraes Narcizo
- Instituto de Biociências, Departamento de Fisiologia, Universidade de São Paulo (USP), São Paulo, SP, Brazil
| | - Ricardo Andrade Zampieri
- Instituto de Biociências, Departamento de Fisiologia, Universidade de São Paulo (USP), São Paulo, SP, Brazil
| | - Lucile Maria Floeter-Winter
- Instituto de Biociências, Departamento de Fisiologia, Universidade de São Paulo (USP), São Paulo, SP, Brazil
| | - Renata Guimarães Moreira
- Instituto de Biociências, Departamento de Fisiologia, Universidade de São Paulo (USP), São Paulo, SP, Brazil
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Souza TL, Batschauer AR, Brito PM, Martino-Andrade AJ, Ortolani-Machado CF. Evaluation of testicular structure in mice after exposure to environmentally relevant doses of manganese during critical windows of development. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 207:111537. [PMID: 33254399 DOI: 10.1016/j.ecoenv.2020.111537] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 09/29/2020] [Accepted: 10/16/2020] [Indexed: 06/12/2023]
Abstract
Despite being an essential trace element with great importance for vital metabolic activities, the manganese (Mn) can also cause damage to organ systems. However, data on the effect of this metal on the male reproductive system are limited, especially using relevant doses to human exposure. The present study aimed to evaluate and compare the effects of Mn exposure on the testicular structure of mice. Three experiments were conducted: (I) direct exposure to realistic doses (0.013, 0.13, and 1.3 mg/kg/day of MnCl2); (II) parental and direct exposure to realistic doses (as in experiment I), where the animals were exposed during intrauterine development and from lactation until reproductive maturity; (III) direct exposure to high doses (15, 30, and 60 mg/kg/day of MnCl2). Biometric, histopathological, histomorphometric and stereological parameters of the testis were evaluated, in addition to sperm morphology. Bioinformatic analyses were performed to identify potential Mn binding sites in 3β-HSD and P450ssc, as well as their protein-protein interaction network. The results obtained were compared using the integrated biomarker response index (IBR). There was an increase of seminiferous tubules pathologies in all experimental conditions tested, with effects on tubular volume, as well as a reduction in tubular diameter. The IBR analyses showed that parental and direct exposure had a significant negative effect on the testicular structure due to the exposure of this metal to sensitive periods of animal development. This study suggests that Mn has the potential to alter the morphological parameters of the testes, affecting the spermatogenesis in mice.
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Affiliation(s)
- Tugstênio L Souza
- Laboratory of Embryotoxicology, Department of Cell Biology, Federal University of Paraná, Curitiba, PR, Brazil.
| | - Amândia R Batschauer
- Laboratory of Embryotoxicology, Department of Cell Biology, Federal University of Paraná, Curitiba, PR, Brazil
| | - Patricia M Brito
- Laboratory of Cell Toxicology, Department of Cell Biology, Federal University of Paraná, Curitiba, PR, Brazil
| | - Anderson J Martino-Andrade
- Laboratory of Endocrine Physiology and Animal Reproduction, Department of Physiology, Federal University of Paraná, Curitiba, PR, Brazil
| | - Claudia F Ortolani-Machado
- Laboratory of Embryotoxicology, Department of Cell Biology, Federal University of Paraná, Curitiba, PR, Brazil
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Correlations between Basal Trace Minerals and Hormones in Middle and Long-Distance High-Level Male Runners. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17249473. [PMID: 33348799 PMCID: PMC7765843 DOI: 10.3390/ijerph17249473] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 12/09/2020] [Accepted: 12/16/2020] [Indexed: 12/16/2022]
Abstract
Several essential trace minerals play an important role in the endocrine system; however, toxic trace minerals have a disruptive effect. The aim of this research was to determine basal concentrations and the possible correlations between trace minerals in plasma and several plasma hormones in runners. Sixty high-level male endurance runners (21 ± 3 years; 1.77 ± 0.05 m; 64.97 ± 7.36 kg) participated in the present study. Plasma hormones were analyzed using an enzyme-linked immunosorbent assay (ELISA) and plasma trace minerals were analyzed with inductively coupled plasma mass spectrometry (ICP-MS). Correlations and simple linear regression were used to assess the association between trace minerals and hormones. Plasma testosterone concentrations were inversely correlated with manganese (r = -0.543; β = -0.410; p < 0.01), selenium (r = -0.292; β = -0.024; p < 0.05), vanadium (r = -0.406; β = -1.278; p < 0.01), arsenic (r = -0.336; β = -0.142; p < 0.05), and lead (r = -0.385; β = -0.418; p < 0.01). Plasma luteinizing hormone (LH) levels were positively correlated with arsenic (r = 0.298; β = 0.327; p < 0.05) and cesium (r = 0.305; β = 2.272; p < 0.05), and negatively correlated with vanadium (r = -0.303; β = -2.467; p < 0.05). Moreover, cortisol concentrations showed significant positive correlations with cadmium (r = 0.291; β = 209.01; p < 0.05). Finally, insulin concentrations were inversely related to vanadium (r = -0.359; β = -3.982; p < 0.05). In conclusion, endurance runners living in areas with high environmental levels of toxic minerals should check their concentrations of anabolic hormones.
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Souza TL, Batschauer AR, Brito PM, Leão-Buchir J, Spercoski KM, Neto FF, Martino-Andrade AJ, Ortolani-Machado CF. Evaluation of Mn exposure in the male reproductive system and its relationship with reproductive dysfunction in mice. Toxicology 2020; 441:152504. [DOI: 10.1016/j.tox.2020.152504] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 04/24/2020] [Accepted: 05/18/2020] [Indexed: 12/16/2022]
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Owumi SE, Danso OF, Nwozo SO. Gallic acid and omega‐3 fatty acids mitigate epididymal and testicular toxicity in manganese‐treated rats. Andrologia 2020; 52:e13630. [DOI: 10.1111/and.13630] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 02/15/2020] [Accepted: 04/12/2020] [Indexed: 12/16/2022] Open
Affiliation(s)
- Solomon E. Owumi
- Cancer Research and Molecular Biology Laboratories Department of Biochemistry Faculty of Basic Medical Sciences University of Ibadan Ibadan Nigeria
| | - Olabisi F. Danso
- Industrial and Nutritional Biochemistry Department of Biochemistry Faculty of Basic Medical Sciences University of Ibadan Ibadan Nigeria
| | - Sarah O. Nwozo
- Industrial and Nutritional Biochemistry Department of Biochemistry Faculty of Basic Medical Sciences University of Ibadan Ibadan Nigeria
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8
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Souza TL, Batschauer AR, Brito PM, Oliveira Ribeiro CA, Martino-Andrade AJ, Ortolani-Machado CF. Multigenerational analysis of the functional status of male reproductive system in mice after exposure to realistic doses of manganese. Food Chem Toxicol 2019; 133:110763. [DOI: 10.1016/j.fct.2019.110763] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 08/09/2019] [Accepted: 08/15/2019] [Indexed: 12/16/2022]
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Yan X, He B, Liu L, Qu G, Shi J, Liao C, Hu L, Jiang G. Organotin exposure stimulates steroidogenesis in H295R Cell via cAMP pathway. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2018; 156:148-153. [PMID: 29549738 DOI: 10.1016/j.ecoenv.2018.03.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 03/07/2018] [Accepted: 03/07/2018] [Indexed: 06/08/2023]
Abstract
Organotin compounds (OTs) are used in a range of industrial products, such as antifouling paints, agricultural pesticides and stabilizers. Owing to potential endocrine-disrupting effects, human exposure to such compounds is a concern. Nevertheless, little is known about the adverse effect of OTs on adrenocortical function in organisms. In this study, the human adrenocortical carcinoma cell (H295R) model was used to investigate effects of OTs on steroidogenesis and potential causes for such endocrine disruption was examined. H295R cells were exposed to several commonly used OTs, including triphenyltin (TPT), tributyltin (TBT), dibutyltin (DBT), and monobutyltin (MBT), and the production level of steroid hormones were quantified. TPT and TBT decreased the production levels of 17β-estradiol, aldosterone, and cortisol, but increased that of testosterone. Furthermore, the expression levels of ten major steroidogenic genes (HMGR, StAR, CYP11A1, 3βHSD2, CYP17, CYP19A1, CYP21, CYP11B1, CYP11B2, and 17βHSD) were examined and both up-regulation of CYP11B2 and down-regulation of StAR, 3βHSD2, CYP19A1, CYP21 and CYP11B1 by TPT and TBT were observed. Intracellular levels of ATP and cyclic adenosine monophosphate (cAMP) and the activity of adenylate cyclase (AC) decreased in the H295R cells treated with TPT and TBT. No obvious changes in H295R were found with the treatment of DBT and MBT. These results suggest that OTs may stimulate steroidogenesis in vitro via inhibition of cAMP signaling pathway.
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Affiliation(s)
- Xueting Yan
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bin He
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Lihong Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guangbo Qu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jianbo Shi
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chunyang Liao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ligang Hu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Institute of Environment and Health, Jianghan University, Wuhan, Hubei 430056, China.
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
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Nkpaa KW, Amadi BA, Adedara IA, Wegwu MO, Farombi EO. Ethanol exacerbates manganese - induced functional alterations along the hypothalamic-pituitary-gonadal axis of male rats. Neurosci Lett 2018; 684:47-54. [PMID: 29981877 DOI: 10.1016/j.neulet.2018.07.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 06/29/2018] [Accepted: 07/05/2018] [Indexed: 11/24/2022]
Abstract
Manganese (Mn) exposure has been reported to induce reproductive dysfunction in animal and humans. Studies have shown that a large percentage of adolescent and adult populations tend to consume alcohol in a binge pattern. However, there is no information on the influence of alcohol on Mn - induced functional alteration along the hypothalamic - pituitary - gonadal axis. This study aimed to evaluate the influence of ethanol (EtOH) on Mn - induced functional alteration along the hypothalamic - pituitary - gonadal axis. Rats were exposed to Mn alone at 30 mg/kg body weight or co-expose with EtOH at 1.25 and 5 g/kg body weight for 35 consecutive days. Results showed that EtOH exposure significantly (p ≤ 0.05) exacerbated Mn - induced decrease in antioxidant enzymes activities, glutathione level and increased oxidative stress biomarkers in the hypothalamus, testes an epididymis of the exposed rats. Moreover, induction of inflammation was associated with disruption of histo-architecture of the hypothalamus, testes and epididymis of rats treated with Mn alone, EtOH alone or in combination. Furthermore, EtOH significantly exacerbated Mn - induced diminution in reproductive hormones and marker enzymes of testicular functions coupled with decreased sperm quantity and quality. Taken together, EtOH exacerbates Mn - induced functional alteration along the hypothalamic - pituitary - gonadal axis in rats via mechanisms involving induction of oxidative/nitrosative stress, lipid peroxidation and inflammation in rats.
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Affiliation(s)
- Kpobari W Nkpaa
- Environmental Toxicology Unit, Department of Biochemistry, Faculty of Science, University of Port Harcourt, P.M.B 5323, Choba, Rivers State, Nigeria.
| | - Benjamin A Amadi
- Environmental Toxicology Unit, Department of Biochemistry, Faculty of Science, University of Port Harcourt, P.M.B 5323, Choba, Rivers State, Nigeria
| | - Isaac A Adedara
- Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Matthew O Wegwu
- Environmental Toxicology Unit, Department of Biochemistry, Faculty of Science, University of Port Harcourt, P.M.B 5323, Choba, Rivers State, Nigeria.
| | - Ebenezer O Farombi
- Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria
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Kanimozhi V, Palanivel K, Akbarsha MA, Kadalmani B. Molecular mechanisms of tributyltin-induced alterations in cholesterol homeostasis and steroidogenesis in hamster testis: In vivo and in vitro studies. J Cell Biochem 2018; 119:4021-4037. [PMID: 29231996 DOI: 10.1002/jcb.26564] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Accepted: 12/05/2017] [Indexed: 12/13/2022]
Abstract
Tributyltins (TBT) are ubiquitous and persistent environmental contaminants that disturb normal endocrine function including gonadal function in humans and marine organisms. TBT was administered through oral route to male Syrian hamsters at daily doses of 50, 100, and 150 ppm/kg for 65 days. Changes in testis morphology, immunohistochemistry of iNOS, 3β-HSD, and 17β-HSD, cholesterol transport receptor, nuclear receptors, and transcription factors were analyzed. TBT treatment affected each of these parameters to significant levels in a dose-dependent manner compared to vehicle treated control. Real-time PCR and protein analyses revealed that expression levels of ApoE and LDL-R mRNA were up-regulated in the testis of TBT-treated animals while the expression levels of SR-B1, LXR, PPARs α, β, and γ, SCAP, SREBP 1 and 2, 3β-HSD, 17β-HSD, CYP17A1, and P450SCC were down-regulated. Leydig cells were isolated and separated adopting percoll gradient centrifugation under aseptic condition. The viability of Leydig cell was affected by TBT treatment in a dose- and time-dependent manner. Further, the mechanism of action of TBT was ascertained by siRNA transfection of ApoE, which was upregulated, and SREBP, which was down-regulated. These observations led us to infer that exposure to TBT hinders intracellular cholesterol transport resulting in abnormal sex steroid biosynthesis and alteration of steroidogenic enzyme activities. Finally, we could recognize ApoE and SREBP as the major factors regulating genes that control cholesterol biosynthesis and steroidogenesis that ultimately inhibit the synthesis of testosterone. Therefore, ApoE is one of the important molecular targets that can be intercepted in context of male infertility/male contraception.
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Affiliation(s)
- Veerasamy Kanimozhi
- Department of Animal Science, Bharathidasan University, Tiruchirappalli, India
| | - Kandasamy Palanivel
- Department of Animal Science, Bharathidasan University, Tiruchirappalli, India
| | - Mohammad A Akbarsha
- Department of Animal Science, Bharathidasan University, Tiruchirappalli, India.,National Centre for Alternatives to Animal Experiments (NCAAE), Former Mahatma Gandhi-Doerenkamp Centre (MGDC), Bharathidasan University, Tiruchirappalli, India
| | - Balamuthu Kadalmani
- Department of Animal Science, Bharathidasan University, Tiruchirappalli, India
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Adedara IA, Subair TI, Ego VC, Oyediran O, Farombi EO. Chemoprotective role of quercetin in manganese-induced toxicity along the brain-pituitary-testicular axis in rats. Chem Biol Interact 2016; 263:88-98. [PMID: 28040552 DOI: 10.1016/j.cbi.2016.12.019] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2016] [Revised: 12/09/2016] [Accepted: 12/22/2016] [Indexed: 01/06/2023]
Abstract
Reproductive dysfunction in response to manganese exposure has been reported in humans and animals. Quercetin, a bioflavonoid widely distributed in fruits, vegetables and beverages has been shown to possess antioxidant, anti-inflammatory and anti-apoptotic activities in different experimental model systems. However, there is dearth of scientific information on the influence of quercetin on manganese-induced reproductive toxicity. This study was designed to evaluate the influence of quercetin on manganese-induced functional alterations along the brain-pituitary- testicular axis in rats. Manganese was administered alone at 15 mg/kg body weight or orally co-treated with quercetin at 10 and 20 mg/kg body weight for 45 consecutive days. Results indicated that quercetin co-treatment significantly (p < 0.05) inhibited manganese-induced elevation in biomarkers of oxidative stress whereas it increased antioxidant enzymes activities and glutathione level in the brain, testes and epididymis of the treated rats. Furthermore, quercetin mediated suppression of inflammatory indices and caspase-3 activity was accompanied by preservation of histo-architectures of the brain, testes and epididymis in manganese-treated rats. The significant reversal of manganese-induced decreases in reproductive hormones (i.e. luteinizing hormone, follicle-stimulating hormone and testosterone) and testicular activities of acid phosphatase, alkaline phosphatase and lactate dehydrogenase by quercetin was complemented by an increase in sperm quality and quantity in the treated rats. Collectively, quercetin modulated manganese-induced toxicity along the brain-pituitary-testicular axis in rats via its intrinsic antioxidant, anti-inflammatory and anti-apoptotic activities, and may thus represent a potential pharmacological agent against manganese-induced male reproductive deficits in humans.
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Affiliation(s)
- Isaac A Adedara
- Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria.
| | - Temitayo I Subair
- Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Valerie C Ego
- Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Oluwasetemi Oyediran
- Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Ebenezer O Farombi
- Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria
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Karimian A, Ahmadi Y, Yousefi B. Multiple functions of p21 in cell cycle, apoptosis and transcriptional regulation after DNA damage. DNA Repair (Amst) 2016; 42:63-71. [PMID: 27156098 DOI: 10.1016/j.dnarep.2016.04.008] [Citation(s) in RCA: 707] [Impact Index Per Article: 88.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 04/19/2016] [Accepted: 04/19/2016] [Indexed: 12/13/2022]
Abstract
An appropriate control over cell cycle progression depends on many factors. Cyclin-dependent kinase (CDK) inhibitor p21 (also known as p21(WAF1/Cip1)) is one of these factors that promote cell cycle arrest in response to a variety of stimuli. The inhibitory effect of P21 on cell cycle progression correlates with its nuclear localization. P21 can be induced by both p53-dependent and p53-independent mechanisms. Some other important functions attributed to p21 include transcriptional regulation, modulation or inhibition of apoptosis. These functions are largely dependent on direct p21/protein interactions and also on p21 subcellular localizations. In addition, p21 can play a role in DNA repair by interacting with proliferating cell nuclear antigen (PCNA). In this review, we will focus on the multiple functions of p21 in cell cycle regulation, apoptosis and gene transcription after DNA damage and briefly discuss the pathways and factors that have critical roles in p21 expression and activity.
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Affiliation(s)
- Ansar Karimian
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Clinical Biochemistry and Laboratory Medicine, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Yasin Ahmadi
- Department of Clinical Biochemistry and Laboratory Medicine, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Bahman Yousefi
- Department of Clinical Biochemistry and Laboratory Medicine, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran; Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
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Wang T, Li X, Yang D, Zhang H, Zhao P, Fu J, Yao B, Zhou Z. ER stress and ER stress-mediated apoptosis are involved in manganese-induced neurotoxicity in the rat striatum in vivo. Neurotoxicology 2015; 48:109-19. [PMID: 25732873 DOI: 10.1016/j.neuro.2015.02.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Revised: 01/14/2015] [Accepted: 02/20/2015] [Indexed: 11/28/2022]
Abstract
Manganese (Mn) is an essential trace element found in many enzymes, however, excessive Mn-exposure can result in manganism which is similar to Parkinson's movement disorder. The mechanisms of manganism are not well-known. The present in vivo study was carried out to determine whether endoplasmic reticulum stress (ER stress) and ER stress-mediated apoptosis are involved in manganese-induced neurotoxicity. Sixty-four SD rats were randomly divided into four groups and were administered intraperitoneally with normal saline (NS, as control) or MnCl₂ (7.5, 15 and 30 mg/kg body weight, respectively) for 4 weeks. We found that MnCl₂ dose-dependently accumulate in striatal. HE staining and TUNEL assay results indicated that MnCl₂ induced striatal neurocytes apoptosis in both male and female rats. The alterations of ultrastructures showed that MnCl₂ resulted in chromatin condensation, mitochondria and ER tumefaction in rat striatal neurocytes. Furthermore, MnCl₂ increased the expressions of p-IRE-1, ATF-6α, PERK, GRP78, Sigma-1R, CHOP, Bim, Bax, caspase-12 and caspase-3, and decreased the expression of Bcl-2 in rat striatal neurocytes. In conclusion, MnCl₂ could induce ER stress and ER stress-mediated apoptosis in rat striatal neurocytes, which might be one of the important mechanisms of Mn-induced neurotoxicity.
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Affiliation(s)
- Ting Wang
- Department of Toxicology, School of Public Health, Peking University Health Science Center, Beijing 100191, PR China; Beijing Key Laboratory of Toxicological Research and Risk Assessment for Food Safety, School of Public Health, Peking University Health Science Center, Beijing 100191, PR China; The seventh people hospital of Zhengzhou, Zhengzhou Henan 450000, China
| | - Xuehui Li
- Department of Toxicology, School of Public Health, Peking University Health Science Center, Beijing 100191, PR China; Beijing Key Laboratory of Toxicological Research and Risk Assessment for Food Safety, School of Public Health, Peking University Health Science Center, Beijing 100191, PR China
| | - Dongxu Yang
- Department of Toxicology, School of Public Health, Peking University Health Science Center, Beijing 100191, PR China
| | - Hongtao Zhang
- Department of Toxicology, School of Public Health, Peking University Health Science Center, Beijing 100191, PR China; Beijing Key Laboratory of Toxicological Research and Risk Assessment for Food Safety, School of Public Health, Peking University Health Science Center, Beijing 100191, PR China
| | - Peng Zhao
- Department of Toxicology, School of Public Health, Peking University Health Science Center, Beijing 100191, PR China; Beijing Key Laboratory of Toxicological Research and Risk Assessment for Food Safety, School of Public Health, Peking University Health Science Center, Beijing 100191, PR China
| | - Juanling Fu
- Department of Toxicology, School of Public Health, Peking University Health Science Center, Beijing 100191, PR China
| | - Biyun Yao
- Department of Toxicology, School of Public Health, Peking University Health Science Center, Beijing 100191, PR China; Beijing Key Laboratory of Toxicological Research and Risk Assessment for Food Safety, School of Public Health, Peking University Health Science Center, Beijing 100191, PR China.
| | - Zongcan Zhou
- Department of Toxicology, School of Public Health, Peking University Health Science Center, Beijing 100191, PR China.
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15
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Associations of urinary metal concentrations and circulating testosterone in Chinese men. Reprod Toxicol 2013; 41:109-14. [PMID: 23791927 DOI: 10.1016/j.reprotox.2013.06.062] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Revised: 05/20/2013] [Accepted: 06/08/2013] [Indexed: 11/23/2022]
Abstract
Toxicological studies have shown that metals directly or indirectly influence testosterone (T) production, but the data from humans is limited and inconsistent. The aim of this study was to examine the associations between urinary metal concentrations and circulating T in Chinese men. Urinary concentrations of 13 metals (arsenic, cadmium, cobalt, chromium, copper, iron, lead, manganese, molybdenum, mercury, nickel, selenium and zinc) and serum levels of T were analyzed in 118 men from an infertility clinic. Multivariable linear regression was used to assess the effect of metals exposure on T. Among the measured metals, the median urinary Zn (359.36μg/g creatinine) and Co (0.16μg/g creatinine) concentrations were the highest and the lowest, respectively. Significant dose-response relationships were found between decreased T and urinary Mn and Zn, even when considering multiple metals (both P for trend <0.05). Our results indicate that elevated Mn and Zn are inversely associated with T production.
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16
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Zhao F, Zhang JB, Cai TJ, Liu XQ, Liu MC, Ke T, Chen JY, Luo WJ. Manganese induces p21 expression in PC12 cells at the transcriptional level. Neuroscience 2012; 215:184-95. [PMID: 22542671 DOI: 10.1016/j.neuroscience.2012.04.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2012] [Revised: 04/01/2012] [Accepted: 04/13/2012] [Indexed: 01/28/2023]
Abstract
Manganese is a common environmental and occupational pollutant. Excessive intake of manganese can cause toxicity known as manganism. Recently it has been demonstrated that unusual expression of cell cycle proteins and aberrant cell cycle progression in the central nervous system are involved in the pathogenesis of neurodegenerative diseases. The present studies were initiated to investigate whether p21 are induced after manganese exposure and its potential effects in vitro, with particular attention being given to understand the underlying regulatory mechanism of p21 induction by manganese in this process. We found that manganese induced DAergic cells injury and upregulation of p21 levels in nigrostriatal regions. Treatment of the PC12 cells with manganese resulted in a time- and concentration-dependent loss of cell viability. Analysis of cell cycle profile indicated that manganese blocked cell cycle progression by arresting the cell cycle at G2/M phase. Moreover, manganese treatment resulted in an increase in the mRNA and protein levels of p21, but did not have the same effect on other related factors. Silencing p21 by RNA interference showed a marked reversal of both G2/M arrest and the decrease in cell viability induced by manganese. Manganese did not stabilize the p21 protein and mRNA, and caused a marked increase in p21 mRNA levels together with an increase in its promoter activity, indicating a transcriptional mechanism. Overall, the in vivo and in vitro data suggest that exposure to manganese can increase p21 levels. An altered cell cycle status of PC12 cells can be induced by manganese through p21 up-regulation, and the induction of p21 occurs at the transcriptional level via promoter activation and mRNA induction.
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Affiliation(s)
- F Zhao
- Department of Occupational and Environmental Health and The Ministry of Education Key Laboratory of Hazard Assessment and Control in Special Operational Environment, Fourth Military Medical University, Xi'an 710032, China
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17
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Tsagué Manfo FP, Chao WF, Moundipa PF, Pugeat M, Wang PS. Effects of maneb on testosterone release in male rats. Drug Chem Toxicol 2011; 34:120-8. [DOI: 10.3109/01480545.2010.482589] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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18
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Meeker JD, Rossano MG, Protas B, Padmanahban V, Diamond MP, Puscheck E, Daly D, Paneth N, Wirth JJ. Environmental exposure to metals and male reproductive hormones: circulating testosterone is inversely associated with blood molybdenum. Fertil Steril 2010; 93:130-40. [PMID: 18990371 PMCID: PMC2823119 DOI: 10.1016/j.fertnstert.2008.09.044] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2008] [Revised: 09/04/2008] [Accepted: 09/09/2008] [Indexed: 10/21/2022]
Abstract
OBJECTIVE To explore associations between exposure to metals and male reproductive hormone levels. DESIGN Cross-sectional epidemiology study with adjustment for potential confounders. SETTING University Medical Center. PATIENT(S) Men recruited through two infertility clinics in Michigan. INTERVENTION(S) Metal concentrations and reproductive hormone levels were measured in blood samples collected from 219 men. MAIN OUTCOME MEASURE(S) Serum FSH, LH, inhibin B, T, and sex hormone-binding globulin levels. RESULT(S) Cadmium, copper, and lead were all significantly or suggestively positively associated with T when modeled individually, findings that are consistent with limited previous human and animal studies. Conversely, molybdenum was associated with reduced T. A significant inverse trend between molybdenum and T remained when additionally considering other metals in the model, and a positive association between T and zinc was also found. Finally, in exploratory analysis there was evidence for an interaction between molybdenum and zinc, whereby high molybdenum was associated with a 37% reduction in T (relative to the population median level) among men with low zinc. CONCLUSION(S) Although reductions in T and reproductive toxicity after molybdenum exposure have been previously demonstrated in animal studies, more research is needed to determine whether molybdenum poses a risk to human reproductive health.
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Affiliation(s)
- John D Meeker
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan 48109, USA.
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19
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Zhao P, Zhong W, Ying X, Yuan Z, Fu J, Zhou Z. Manganese chloride-induced G0/G1 and S phase arrest in A549 cells. Toxicology 2008; 250:39-46. [PMID: 18577415 DOI: 10.1016/j.tox.2008.05.016] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2008] [Revised: 05/25/2008] [Accepted: 05/26/2008] [Indexed: 10/22/2022]
Abstract
In the present study, we investigated the effects of manganese chloride (MnCl2) on cell cycle progression in A549 cells used as a model of Mn-induced lung toxicity. Cells were treated with various concentrations of MnCl2 (0, 0.01, 0.1, 0.5, 1.0 or 2.0 mM) for 24, 48 or 72 h. Cell proliferation was determined with MTT assay and mitotic index measurement and apoptosis was measured by flow cytometer. The results showed that MnCl2 inhibited A549 cells proliferation in a dose- and time-dependent manner, and induced apoptosis in A549 cells. When G0/G1 cells obtained by serum starvation were incubated with 0.5 mM of MnCl2 in the presence of 10% serum for several time intervals, the disruption of cell cycle progression was observed. The G0/G1 arrest was induced by MnCl2 treatment at 16 h and the arrest maintained for 8 h. Following the G0/G1 arrest, MnCl2 blocked the cells at S phase at 28 h and the S phase arrest maintained for at least 4 h. And moreover, proteasome inhibitor MG132 was able to prolong the duration of G0/G1 arrest induced by MnCl2 treatment. Results of western blotting assay revealed that cellular Cdk4, Cdk2 and phospho-Cdk2 (Thr160) levels decreased in manganese-treated cells at both 20 and 28 h. In addition, the decreasing of Cyclin A level and the increasing of p53 and WAF1/p21 were also induced by MnCl2 treatment at 20 h. The expression of Cyclin D1, Cyclin E and Cdc25A proteins was not altered in manganese-treated cells at both 20 and 28 h. Our results indicate that MnCl2 orderly induces G0/G1 and S phase arrest in A549 cells, the decreasing of Cdk4, Cdk2 and Cyclin A, and the increasing of p53 and Cdks inhibitor WAF1/p21 might be responsible for the G0/G1 arrest, and the decreasing of Cdk4 and Cdk2 levels for the S phase arrest.
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Affiliation(s)
- Peng Zhao
- Department of Toxicology, Peking University Health Science Center, Beijing 100083, China
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20
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Rovetta F, Catalani S, Steimberg N, Boniotti J, Gilberti ME, Mariggiò MA, Mazzoleni G. Organ-specific manganese toxicity: a comparative in vitro study on five cellular models exposed to MnCl2. Toxicol In Vitro 2007; 21:284-92. [PMID: 17055213 DOI: 10.1016/j.tiv.2006.08.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2006] [Revised: 08/01/2006] [Accepted: 08/31/2006] [Indexed: 11/20/2022]
Abstract
Manganese (Mn) is both an essential nutrient and a toxicant, with specific effects on liver and kidney (acute exposure) and on central nervous system (CNS) (chronic exposure). Mn neurotoxicity includes neurobehavioral disorders and extra-pyramidal motor dysfunctions (manganism), possibly due to focal injuries to the basal ganglia. Even if widely investigated, the molecular mechanisms responsible for Mn toxicity remain to be clarified. Aim of this study was to identify suitable in vitro models to investigate these molecular pathways. To this purpose we compared the effect of manganese chloride on four cell lines, representative of the main target organs of Mn toxicity in vivo. HepG2 and MDCK cell lines were selected for liver and kidney, respectively; glial GL15 and neuronal SHSY5Y cells were used as models of CNS components. To complete the "motor system" model, skeletal muscle C2C12 cells were also included. Our results demonstrate that hepatic, renal, glial and neuronal cell types differently react to Mn, mirroring the specific in vivo response of the tissue they represent. This confirms their value as suitable in vitro models to study Mn-related toxic events. Interestingly, also muscle C2C12 cells showed a noticeable sensitivity to Mn, preferential targets being differentiated myotubes.
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Affiliation(s)
- F Rovetta
- University of Brescia, Department of Biomedical Sciences and Biotechnologies, Italy
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21
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Zhuang Z, Pei Z, Chen J. Infrasound-induced changes on sexual behavior in male rats and some underlying mechanisms. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2007; 23:111-114. [PMID: 21783744 DOI: 10.1016/j.etap.2006.07.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2006] [Revised: 07/20/2006] [Accepted: 07/31/2006] [Indexed: 05/31/2023]
Abstract
To investigate some bioeffects of infrasound on copulation as well as underlying mechanisms, we inspected the changes of sexual behavior, serum testosterone concentration and mRNA expression levels of steroidogenic factor 1 (SF-1), steroidogenic acute regulatory protein (StAR) and cytochrome P450 cholesterol side chain cleavage enzyme (P450scc) in testes of rats exposed to infrasound of 8Hz at 90 or 130dB for 1, 7, 14 and 21 days (2h/day), respectively. Rats exposed to 90dB exhibited significant decrement in sexual behavior, serum testosterone levels and mRNA expression levels of StAR and P450scc at the time point of 1 day but not at the rest time points, and no significantly change of SF-1 mRNA expression was observed over the period of 21 days in spite of mild fluctuation. Rats exposed to 130dB exhibited significant decrement in all aspects above, which became more profound with prolonged exposure. Our conclusion is that adverse bioeffects of infrasound on reproduction depend on some exposure parameters, the mechanism of which could involve in the decreased expression of some key enzymes or regulator for testosterone biosynthesis.
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Affiliation(s)
- Zhiqiang Zhuang
- Department of Physical Therapy and Rehabilitation of Xijing Hospital, The Fourth Military Medical University, No. 17, Changle Western Road, Xi'an, Shaanxi Province 710032, PR China
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22
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Colón E, Zaman F, Axelson M, Larsson O, Carlsson-Skwirut C, Svechnikov KV, Söder O. Insulin-like growth factor-I is an important antiapoptotic factor for rat leydig cells during postnatal development. Endocrinology 2007; 148:128-39. [PMID: 17023532 DOI: 10.1210/en.2006-0835] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The present investigation examines the influence of IGF-I and the role of IGF-I receptor (IGF-IR) in the apoptosis/survival of Leydig cells. Immunohistochemical analysis of the rat testis at different ages revealed that the level of the phosphorylated IGF-IR increases from birth to d 20 of postnatal life, remaining high in the adult testis. Western blotting revealed that this level is higher in Leydig cells isolated from 40-d-old than from 10- or 60-d-old rats. Application of the terminal deoxyribonucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling assay revealed that IGF-I decreases the level of apoptosis in Leydig cells at all stages of development, and the selective inhibitor of IGF-IR, picropodophyllin, blocks this antiapoptotic effect. The mechanism underlying the antiapoptotic action of IGF-I involves the phosphatidylinositol 3-kinase/Akt pathway, and in immature Leydig cells, this growth factor enhances the expression of Bcl-2 and cellular inhibitor of apoptosis proteins 2, while preventing activation of caspase-3 by cleavage. Furthermore, IGF-II and high concentrations of insulin also evoke phosphorylation of IGF-IR and, like IGF-I, enhance the expression of the steroidogenic acute regulatory protein by Leydig cells. Inhibition of IGF-IR by picropodophyllin decreases the survival of Leydig cells, both in the presence and absence of IGF-I, demonstrating that signaling via the IGF-IR plays an important role in Leydig cell survival.
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Affiliation(s)
- Eugenia Colón
- Department of Woman and Child Health, Paediatric Endocrinology Unit, Astrid Lindgren Children's Hospital, Karolinska Institute and University Hospital, SE 17176 Stockholm, Sweden.
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23
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Vautz W, Baumbach JI, Uhde E. Detection of emissions from surfaces using ion mobility spectrometry. Anal Bioanal Chem 2006; 384:980-6. [PMID: 16402176 DOI: 10.1007/s00216-005-0240-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2005] [Revised: 11/15/2005] [Accepted: 11/16/2005] [Indexed: 11/30/2022]
Abstract
Emissions from surfaces (from furniture, wall paintings or floor coverings for instance) significantly influence indoor air quality and therefore the wellbeing or even the health of the occupants. Together with metabolites from mold they are responsible for the well-known "sick building syndrome". Therefore, it is in the interest of the manufacturer as well as of the occupants to have a fast and accurate method for the detection of substances relevant to this syndrome in order to be able to monitor and control product quality and indoor air quality. The use of small and easy-to-transport ion mobility spectrometers that use UV light as the ionization source enables rapid in situ detection of such substances with high selectivity and sensitivity (detection limits in the lower ppb range). If a multicapillary column is used for preseparation as well, the selectivity is increased and the unwanted influence of humidity on the spectra can be eliminated, thus enabling the use of the instruments under normal ambient conditions. Furthermore, the use of air as carrier gas avoids the need for other sources of high-purity gas. An emission cell with a homogeneous and constant air flow over the surface to be investigated was developed in order to ensure reproducible results. Investigations of emissions from wooden surfaces with and without additional contamination as well as from complex mixtures are presented. The results demonstrate that relevant emissions can be identified and quantified with high sensitivity and selectivity in under five minutes. Therefore, the method is useful for indoor air quality monitoring, especially when miniaturized instruments are applied.
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Affiliation(s)
- Wolfgang Vautz
- Institute for Analytical Sciences (ISAS), Bunsen-Kirchhoff Str. 11, 44139, Dortmund, Germany.
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